This 306 page book is an excellent summary of the status of scientific knowledge of anxiety disorders at the beginning of the 21st century. Helen Saul (the author) is a scientific journalist, and writes for a general audience. The book is comprehensive in scope, as revealed by the chapter titles: "History," "Evolution," "Genetics," "Neurophysiology," "Behavior," Cognition," "Personality and Temperament," "Gender and Hormones," "Light and Electromagnetism," and "A Physical Problem." Those who want to check her sources can consult the "Further Reading" section at the end of the book.
One thing I gleaned from this book is the wide diversity of anxiety disorders. It's likely that syndromes that are combined together into a single disorder (e.g. panic disorder) have different etiologies. Since we can only diagnose anxiety disorders based on symptoms, we are certainly combining different disorders into one "package." It is similar to headaches. A headache is a symptom, but it can be caused by many different things (e.g. migraines, tension, stroke, brain tumor, etc.) Similarly for panic disorder and other anxiety disorders.
The main reason I read this book was for the information included in the "Light and Electromagnetism" chapter. Saul begins the chapter with a section called "Mary's Story." Mary Dwarka is an agoraphobic housewife who developed an original hypothesis about her disorder. (Agoraphobia is a fear of public places and open spaces, sometimes associated with panic attacks.) Dwarka believes that agoraphobia is basically a travel disorder, a disruption of our navigational ability. People suffering from this disorder get disoriented when trying to use modern transport systems. "It could be due to the magnetic fields set up by subway or electric train systems, the artificial lighting on almost all public transport, or even just the sheer speed and distances covered. Whatever the underlying reason, it is the disorientation, rather than anxiety, that triggers the panic reaction" (p. 228). Agoraphobics are also upset by the lack of an escape route. If you're on a train, you can't get off until it stops at the next station. If you're traveling in a car on a highway, you have to wait until the next exit to get out. Our Stone Age ancestors wouldn't have been so confined as they wandered through the forests and jungles. Dwarka attributes the fact that women are 2 to 3 times more likely than men to have agoraphobia to fluctuating hormones. Her symptoms, as those of some other women, went into remission during her pregnancy.
Saul then summarizes Robin Baker's human magnetoreception research. Baker, working in the 1970's and 1980's, was a pioneer in the study of human magnetoreception. It must be remembered that Baker studied normal subjects, and wasn't specifically interested in the application of magnetoreception to psychiatric disorders. Saul mentions his research as support for Mary Dwarka's hypothesis.
Saul next turns to the effects of light on anxiety disorders. She mentions the research of Arnold Wilkins, who studied the effects of fluorescent lights on several medical conditions, including epilepsy. Some people are very sensitive to fluorescent lighting, TV's, and strobe lights. This sensitivity can take the form of seizures.
Agoraphobics are sensitive to sunlight. The Greek physician Hippocrates wrote of sunlight sensitivity 2400 years ago. A third of agoraphobics wear sunglasses or prefer to go out in the dark. Many are particularly sensitive to fluorescent lighting. Wilkins found that strip lights, glare, bright sunshine, and sunlight broken by trees or railings are troublesome for agoraphobics.
Saul mentions some alternative magnetic treatments like Empulse and Transcranial Magnetic Stimulation (TMS). Both of them seem to help some people with anxiety disorders, but evidence is not conclusive. It must be remembered that they produce artificial magnetic fields that are many times more powerful than the geomagnetic field. They are as unnatural as drugs.
One problem with the book is that it is entirely text. Saul is an excellent writer, and I didn't have a problem following it, but I have a background in psychology. Saul would have made the book accessible to a wider audience if she had included some pictures, charts, and tables.
I winced when I read the sentence: "I. P. Pavlov . . . was an early learning theorist in the 1940s whose dogs famously heard a bell before receiving food" (p. 139). Pavlov died in 1936.
I recommend this book as a readable introduction to the science and treatment of anxiety disorders. I commend Saul for her willingness to talk about subjects like light and electromagnetism, subjects that mainstream scientists avoid like the plague.